Video 4:57
North Korea escalates tensions

Michael RowlandUpdated
Thu 4 Apr 2013, 2:09 PM AEDT

North Korea's decision to block access to a key joint industrial zone with South Korea is the latest move in an escalating military crisis in that region. President of global security foundation Ploughshares Fund, Joe Cirincione, spoke to News Breakfast about North Korea's motivations.